Draft-gear.



W. H. COTTON& T. D. HENDERSON. L. J. SMITH, ADMTNISTRATOR or T. D. HENDEABSON, DEo'D.

DRAFT GEAR.

APPLICATION FII ED 00T. 11, 1907. 4

i Patented Apr. 18, 1.91 1

a SHEETS-SHEET s.

f UNITED sfrATEs PATENT onirica.

'WALTER'IL' do'r'roN'AND-'rHoMAs D. HENDERSON, oF cincaso, ILLINOIS; LLoYp I. i sMI'rH, or coox ooUN'r/m-ILLINoIs. ADMINISTRATOR or SAID 'rIIoMAs D. His-Nona DRFNGEAB.

Speeicatlenof Letters Patent. -Patented Apr. 18,

l 'Aplineationfnled october 11,1907. sria1Nq.s97,o25.

Toall whom it may concern;

Be itknown that we, WALTER H. Co'rroN and THOMAS D. HENDERSON, citizens'v of the United States, and residents of' Chicago,

'county of Cook,.and State of Illinois, have invented certain new and useful Improvements in Draft-Gears, of which the follow'- ing is a specification and which are illustrated rinthe accompanying drawings, forniing a part thereof. p A The invention relates to that type 'of draft appliances for railway cars commonly known as friction draft gears, 'and in which the stressesdue to either pulling or butling are dissipatedv in part by the frlctional engagement of theslidinfr members. V i

The object of the invention is to secure a.. high degree of .eiciency', not only`in res'isting the initial stress. but in dissipating the recoil.

The invention is exempliiedinthe-struc.`

tu re hereinafter described, and which is illustrated in the .accompanying drawings, in which- Figure 1 is a plan sectionof the draft'gear as applied to the sills of a railway car-shown in the 4positionof inaction.; Fig. 2 is a similari-view, the partsbeing shown in the -position taken when subjected toV pulling stresses; Fig. 3 is a side elevation, partly in section, of the devices shown in F ig, 2; Fig. 4.- is a plan section of the device,the parts being shown in-'the position assumed under butiing stresses; Figs. 5, 6,. 7, S, 9 and10 are details'of various plates and supplementary followers entering into the construction of vthe device. Y

A pair of draft sills is vrepresented at 15, 1,6; a pair ofcheek-plates 17, 18, being applied to the inner faces thereof. The usual' drmr-baris shown at'19, and the tail-strap` f or loop 4attached to the draw-bar and eneirclingthe ldra-ft gear proper is' represented at 2O..A Allof'these parts are ofusua'l construction, except as hereinafter pointed out.

y The springs and friction devices are inclosedwit-hin aV housing, shown asin intef gra 1l casting open at its rearward end, its bodyr u portion 21 being squareand its forward closed end 22 being reduced in size and round iu cross section. The forward 4end of the body portion -21 of this housing constitutes the shoulders 23, 24, for en aging the forward shoulders of the chee-plates 17, 18.

Vquentl within the chamber of the, body portion 21 of the housing, and-between it and the for- .ward end vof the extension 22 of the housing there is located a powerful expansion spring 29. Back -of the follower 28 the housing is filled with a series of fric ion plates and a set of wedging plates. The friction plates are of two forms, arranged in alternationand disposedin two sets, one on either side of the wedging devices, the latter occupying the vertical median plane of the housing.

The. friction plates 30' are providedl 'at Y their upper and lower edges with projecting bosses 31,` 32, adapted to itwithin complementary recesses 33, 434;, in the. top and bottom of the body of the housing, to which they are consequently lockedfagainst'longitudinal movement while' being free to move laterally. The friction plates 35 are of greater length than the plates 30, their length being a' littlel less than the normal distance between the followers 25 and 28, their upper and lower edges are straight and their vertical width is such that the .plates fit loosely between the top and bottom ofthe housing. These latter' Y plates are consey free to move both longitudinally and laterally.

A pair ofI wedge plates 36, 37, having outer faces smooth and their inner faces notched to form a plurality of wedging surfaces 38, inclined outwardly and backvwardly, areV located between the two groups of friction 'plates and in' frictional engagement with the inner member of each group. These wedging plates abut against the rearvward .face of the supplemental follower` 2S.

e l.liever en- Vsurfaces '38 of the members't, 37,'with which they are engaged. The wedge mem ber'39 is constantly in abutting engagement with the-follower and its length 1s s'uch that its forward end is spaced apart from and never engages the follower 28. l

The follower 2S is centrally apertured` as 'shown at 42, and within this aperture 4.is

loosely fitted a cup 43, having its open end `forwardly directed and being provided with a stem 44, projecting backwardly from its closed end and being ,inconstant abutting ,engagement with the-wedge member 39. An

expansion spring 45,i's seated Within the l cup 43 'and reacts between it and the front end of. the' housing extensionV 22. This, spring is of less tension than the spring-29,

. and'is housed within the latter.

, subjected.

, The several shoulders of the cheek-plates i7, 1 8, are undercut, theirl bearing faces being inclined inwardly and backwardly, and

the/shoulders 23, 24, and the outer tace Yof` the follower are complementary in forni, thus interlocking with the 'cheek-plate shoulders and preventing the outward bowing or buckling of the cheek-plates or'draft .sills under the severe stresses to which'tliey'are This featuie is; not herein f claimed as-it is made the subject of a divisional application.

In use the shoulders 23, 24, of the housing.

and the follower 25 are normally in engagenient with the cheek-plate shoulders with' which they coperate, preferably the' sprimgsv having been somewhat compressed ni as# senibling the parts. Under, the influence of pulling'stress the draft gear moves towar and to the position illustrated in Fig. 2 of the drawings. As vthe follower 25 begins t0 advance it carries with it the wedging membei' 39, compressing the spring.45. The fol-V lower 28, being sustained by .the spri'ngr 29,.

remains stationary for `a time, thus prevent-- 'ing the advance ofthe wedge "members 36,

37, and consequently these members'are spread by Vthe engagement of the we'dging surfaces as the central wedge-member ad '\'ances, forcing the Yfriction plates 30, 35,

outwardly against the side walls lot' the housing and increasing the frictional engagement of the various contactingfaces. vVhen the'. friction between the wedging surfaces exceeds tbe tension of the spring 29, the fol? lower 28 moves forward, leaving the friction plates 35. Farther advance of the, follower 25 brings it -into contact with theser plates and advances them into the housing,

this advance, -lio\`\fe..ver, being resisted by the frictional contact of thc-,plates 35 with tbe plates 30, and with the walls of the housing, as well as by the tension ofboth springs. As tbc tension of the spring 29 increases with its compression, and as this compression is transmitted wholly through the wedge members 36.37, the. central wedge member is still Yfarther advanced relatively.

to its companions, thus augmenting tbe lateral pressure upon' the friction plates and coi"|i's|' ondingl'v increasing their friciional c ngag'mnent. ttf follows, therefor-e.V that. 'there is a gradual augmentation ot'v resist- -l ance to tbe pulling stress, conlnu-ncin g, with -cause of. their 0 dV the housing walls .and the p ates 30, T his 'al'n'upt release of the friction tltetension of t-he' inner and develop ing by the addition of the' tension-of theV outer*springend the constantly increasin 'frlctional .engagement of the plates, unt

such resistance exceeds the stress applied" andthe' parts come to rest.

Upon the recoil the wedgin'g member 39 is the first `to move' under theintluence of the spring $45, .thereby reducing the friction between the plates and Vpermitting their f `backward movement under the influence of the spring 29, the preponderating tension ofA this' spring prevents a sudden marked ,diminutionof the friction and insures a gradtion and di'ssipa- 1 ual release and the abso tionV of theload by the rictionz the action proceeding 'correspondingly but'mversel'y of the action .due to the'application of the stress. f

Under'the influence of. bufiing stress, the

' parts are moved toward and-to the positionl 'shown in-Fig. 4. -Atthe outset, as the housing 21 advances the inner spring 45 is compressed, the wedge member 39 being iinmovable because of its abutting contact with the follower 25. The housing earrieswith it the plates 30,'because of itsv positive engagement therewith, and the Vplates 35, be-

frictional enagement with advance movement causes'the compression of the spring 29,and the consequent atlvance movementof the follower 28 and the wedge `members 36, 37 ,-thus ,forcing the frictionV plates laterally and increasing 'the friction between them and between the outer plates and the walls ofthe housing. The ad- Vance of the plates .35 nis stopped byrtlieir contact with the follower25, and further in-.'

ward inovementof thehousingis resisted by the increasing tension of both springs andthe increasingriction of the sliding' parts. The advance movement of the friction members-.36, 371sfvcry small and' in practice, thel parts .being properly tioned as to size and sti'eiigtli,fwill always 'be stopped by the wedging action, ,the fol? lower 2S. never being movedl intoeugagenient with the plates 35 by its adva'nee Yand hence reaching no positive abutment.'

Upon tbe recoil the wcdge'memb'ers 36, 37, move baekwa'rdly, under the intluence of the lateral stress uporithem, supplemented Vby the reaction of the spring 45 on the inner 'end'of tbe'housing, as the tension of thel 'spring 29 is reduced, but-the reaction of this propor-V the friction members 36, 37, forwar the housing backward,'on the other ur ing maintain the friction,l this 'friction meantime urging the plates 35 backwardly against the'follower 28. This balance of vpressure by the reaction of the lar ler spring throws upon the smaller spring t e duty 'of carrying back the draft' riggirngms a. whole, except tlie inner wedge member, 'and by this means effecting the gradual release of the frictional elements.

vWhile theprinciple 'of actionrin the release after biitlinfr differsffrom that of the release after pulling stresses, the movements 'of the parts and the resulting absorption of the stressesl are substantially identical, differing essentially only in that under the inlliience of pulling stresses the plates travel substantially through the entire range of nioveii'i-f'nt. of the draw-bar, the plates 30 remaining stationary, while under the influence ot'- buliing stresses the platesV 30 travel through the entire range of movement of lthe 4draw-bar while the plates 35 remain almost stationary, moving only the Vshort,

distance intervening between their ends and thefollower plate 25, as show n in Fig.V 1.'

The Ldevice is sim le andcheap of con- `struction:aiid`assemb y. -The friction plates may be of sheet metal, our preference is for boiler plate, and machining is unnecessary. 'llie friction Yplates'may be as numerous as the space available and stiffness will per-y mit, andfbecause of their considerable number and extended surface area. the frictional wear is so widely distributed as to be unappreciable except after very long service. The device is readily made of adequate strength .to resist stresses far in excess of.

present day practice, leavingl an adequate and more than adequateffactor of safety. The release, while certain and-quick, 1s,

nevertheless, so gradual, and the dissipation of energy so complete, thatshocks fi'oni recoil areyreduced far below all .possibledan- Vger of injury to the cars and their` contents.

'e claim as our invention'- l. draft gear comprising, in combination` va chainbered follower, a plurality of friction plates carried by and longitudinally movable with the follower, a pluralityof severally-independent floating friction plates interposed between and extending beyond .the first-named plates at both ends, means yieldingly carried hy the' lchambered follower engageable with the inner endsfof the Hoa-ting plates, a follower opposed vto the chambered follower and engageable with the extended ends of the second-named set of tion, a cham 'the friction plates, .and wedging elements independent of plates interposed between groups thereof and actuated by the followers.

A draft gear winprising,'in combinared follower, a pluralityl of friction plates \carried by the follower, a

plurality independent friction plates in- Y terposedbetii-'een and extending at both ends beyond the 'first named plates, a follower opposed Vto the first namedfollower and Ve11- gageable with the ends-of the independent 7(` plates, and a spring reacting against the first named follower and urging the independent plates toward the second named f follower.

3. A draft gear coin'iprising, in combina-V 75 tion, a housing, -a 'plurality of disconnected friction plates mounted within the housing'l andibeing free to move in directions perpendicular to their faces but fixed against longitudinal movement within the housing,

a'second set of disconnected floating plates arranged alternately of and in frictional engagement with and beingr of greater length than the first set of plates, a pair of followers at oppositeends of the two sets of .35,

plates, and interengaging wedging members located between two groups of the plates and engaging, respectively, the two followers. i 1

4. A draft gear con'iprising. in combina.- 90

tion` a housing, a traveling follower within the housing, a. pair of plates located adjacent the. median line of the housing in engagement Vwith the follower and having wedvin surfaces on their ad'aeent faces a 95 b a j follower exterior of thehousing, a plate in engagement with the last-named follower located betweenv the first-named plates and Vhaving wedging surfaces complementary l thereof, two sets of disconnected alternatelyarranged friction plates grouped on opposite sides of the two' first-named plates and being movable in directions perpendicular to their faces, the two sets of such plates being of unequal length, the shorter plates lieing secured against longitudinal movement relative to the housing. a springinterposed between the end of the housing and the firstnamed follower. anda spring interposed be` tween the end of the housing and the centralV 1,10

wedging plate. l 5. A draft gea-r comprising, in combination, a. housing having a. closed end and shoulders for engaging a pair of draft lugs, a follower for enga-ging a second pair,V of draft lugs, a follower within the housing,

cooperating wedging members bearing each inner endl of the.hoii`sling and coperating with\I the wedging member engaging.' the 6. A draft gear coniprising,'in combina- ,l tion, a forward ehambered follower const1- tuting a housing,- a rearward follower, an

",'apertured follower within the housing, a

spring reacting between the inner end of tlie housing and the apertured follower, a wedging plate bearing centrally against the rearward follower, a spring reacting between the inner end of the liousingfand `such wedging plate, a pair of wedging plates engaging the two faces of the 'first-named wedging plate and engaging 'the apertured follower, a set of laterally movable discoiil nected friction plates grouped between the wedging plates and .the side wall s; ,ofthe housing and having shoulders engaging the top and bottom walls thereof, and a sctiof disconnected yfloating friction plates arrangedalternately of and being offgreater length than the members of the first-named setof friction plates.

Y 7. In a draft gear, in combination, front and rear followers engageable with Ythe draft shoulders of a car, the frontfollower bein chainbered two sets of-lonfitudinall g a A n disposed friction plates Vof unequal length located between the followers, the plates of the shorter set being fixed against longitudinal movement as to the front follower, the

lplates of the longerset being engiigeable by the rear follower, wedging plates reacting n on the friction plates, one of the wedging p atesbeing in contact with the rearfollower, a spring reacting between such wedging plate and the forward follower, and a second spring of greater strength Vthan the.

follower, wedgingplates reacting upon the friction plates, one of the wedging plates being in contact with one of the followers, a

Aspring reacting between such wedging plate and the other follower. a transverse. plate engaging thc other wedging plate and engageable. with the longer set of friction i, plates. and aV second spring of greater strength than the Iirst-nanicd spring react in'glietwcen the transverse plafe-and the followcragai-st which the tirst-naii'ied spring v reacts.

9. In a draft gear, in coinbinatioiua -inov-y able housing -liaving draftl lug engaging shoulders, two sets of intercalatiiig discoiinec-ted laterally-movable friction plates inclosed within the housing,the.plates of one set being locked against longitudinal movement relatively as tothe housing and the plates ofthe other set beingI floating, and

normally extendingb'eyond the locked plates at both ends, wedging elementsindependentofthe friction plates and acting laterally thereon, a draft .lug engaging follower engageable witlithe ends of the floating plates, a transverse plate ei-i'gageable with the oppo' site ends of the floating plates, and a sprin reacting between. the transverse plate and the end of tlie'hoiising... 10. In adraft gear, in' combination, a housing shouldered to engage a pair of draft lugs Aand having one end closed, a follower adapted to engage a 'second pair of draft lugs, a set of friction plates within the housing and anchored thereto longitudinally, a

set of floating friction ,plates intercalating with and beinglof greater length than the anchored plates'and engageable with 'the secoiul-iiaincd follower,'th`e two sets of.l friction plat'es being arranged in two groups, wedging plates located' on the median line of the housing and between the two groups offrictionplates, a follower enga cable .with one of the wedging elements an with theinner ends of the floating friction plates, a. spring reacting between the closed end of the hous- Ying and the last-named follower, a spring of lesser tension reactin between .the closed yend of the housing an( the wedgi'ng element coperating with the first-named follower.

l1. A draft gear comprising, in combina; tion, a housing having cheek plate engaging shoulders, and bciiigopen at one end, a set` Vof laterally movable friction plates carried within the housing and anchored against longitudinal movement with reference thereto, a second .set of laterally movable friction platesV interposed between and being of greater length than the members of the firstnamcd set of plates, and being longitudi# nally movable with reference to the housing,

'a' follower beyond the open end of the housing and engageablc with the second-named set of plates, a spring reacting between the second-named set of plates andthe closed end of the housing, and means for augmenting the .frictional contact of the two sets 0f plates. Y

l2. ln a draftA gear, in combination, a housing having draft-lug engaging shoulders and a spring engaging abutment, a set of laterally movable friction plates within `the housing and secured against longitudinalV movement relative' thereto, a second set, Vof

friction plates arranged in alternation with andof greater length than the first-named set Aof friction Vplates and b eing free to move isjo ' sets of friction plates andD of laterally movable Alongitudinally with reference to the housing and normally projecting beyond the end thereof, a follower within the housing and engageable with the innerends of the seci ond-named set of friction lates, a s ring` reacting between vsuch fo ower an the abutment of the housing, a draft-lug engaging follower exterior of the housing and engageable with the second-named friction plates, and a set of coperating wedging elements interposed between 0*roups of the two actuated respec-v tively by thehousing and the last-named follower.

13.` In a draft gear, in' combination, a housing having draft-lug engaging shoulders and a spring engaging abutment, a set friet-ion plates within the housing and secured against longitudinal movement'relative thereto, a second set of friction plates arranged in alternation with and of greater length than the firstnamed set of friction plates and being free to move longitudinally with reference tothe housing and normally projecting beyond'the end thereof, a follower within the housing and engageable with the inner ends of the second-named set of friction plates, a spring reacting between such follower and the abutment of the housing, a draftlug engaging follower exterior of the housing and engageable with the outer ends of the secondnamed friction plates, and a set of coperating wedging plates interposed between groups of the two sets of friction plates, one of such wedging plates being engageable by the follower wit in the housing, the other of such wedging plates being engageable by the follower exterior of the housing, and a' spring reacting between such last-named wedging plate and the abutment of the housing. e

14. Ina draft lgear, in combination, a housingfhaving draft lug engaging shoulders and a spring engaging abutment, a set of laterally movable friction plates within the housing and secured against longitudinal movement relative thereto, a second set of friction plates arranged in alternation .with and of greater length than the first-named set of friction plates and being free to move longitudinall with reference to the housing and norma ly projecting beyond the end thereof, a follower within the housing and engageable -with the inner ends of the friction plates,

'movable friction plates second-named set of friction plates, a spring reacting between such follower and the abutment of the housing, a draft-lug engaging follower exterior of able with the second named friction plates, and a set of coperat-ing wedging plates interposed between groups of the two sets of one of such wedging lates being engageable by the follower within Vthe housing, the other of such wedging plates being engaged by the follower exterior of the housing, and a spring reacting between su'ch last-named wedging late and the abutment of the housing, suc spring being, of less strength than the first-named spring.

l5. In ya draft gear, in combination, a housing having draft lug-engaging shoulders and being closed at one end and open at the other end, two groups of laterallywithin the housing and anchored thereto against longitudinal movement, floating friction plates alternated with and of greater length than the firstnamed plates and normally projecting beyond the open end of the housing, a draft lug-engaging follower facing the open end of the housing, an apertured follower between the friction plates and the closed end of the housing, coperating wedge elements between the groups of plates one thereof engageable by the first-named follower and the other engageable by the second-named follower, a spring reacting between the end of the housing and the second-named follower, and a spring bearing upon the end of the housing and cooperating through the aper-. tured follower with the wedge element en-A gageable by the first-named follower.

16. 'In a draft gear, in combination, a

`housing adapted. to engage draft shoulders,

friction plates carried by the housing and anchored against longitudinal movement the housing and engage- -V relatively thereto, floating friction plates ini terposed between and of greater length than the anchored plates, a pair of followers engageable respectively with opposite ends of the floating plates, cooperating wedging elements independent of the floating plates and acting laterally upon the several friction .plates,'such wedging elements cooperating respectively with the two named followers, and a spring interposed between one of the followers and a .portion of the housing.

WALTER H. COTTON. THOMAS D. HENDERSON.

Witnesses: f K. A. Oos'rELLo, Louis K. GILLsoN. 

